Improve logging in signal filter

qutebrowser/browser/signalfilter.py

@@ -70,9 +70,6 @@ class SignalFilter(QObject):
         """
         sender = self.sender()
         log_signal = not signal.signal.startswith('2cur_progress')
-        if log_signal:
-            logging.debug("signal {} (tab {})".format(
-                dbg_signal(signal, args), self._tabs.indexOf(sender)))
         if not isinstance(sender, WebView):
             # BUG? This should never happen, but it does regularely...
             logging.warn("Got signal {} by {} which is no tab!".format(
@@ -80,8 +77,10 @@ class SignalFilter(QObject):
             return
         if self._tabs.currentWidget() == sender:
             if log_signal:
-                logging.debug("  emitting")
+                logging.debug("emitting: {} (tab {})".format(
+                    dbg_signal(signal, args), self._tabs.indexOf(sender)))
             signal.emit(*args)
         else:
             if log_signal:
-                logging.debug("  ignoring")
+                logging.debug("ignoring: {} (tab {})".format(
+                    dbg_signal(signal, args), self._tabs.indexOf(sender)))

qutebrowser/test/utils/test_signal.py

@@ -47,6 +47,15 @@ class TestDebug(TestCase):
         self.assertEqual(sigutils.dbg_signal(self.signal, [23, 42]),
                          'fake(23, 42)')
 
+    def test_dbg_signal_eliding(self):
+        self.assertEqual(sigutils.dbg_signal(self.signal,
+                                             [12345678901234567890123]),
+                         'fake(1234567890123456789\u2026)')
+
+    def test_dbg_signal_newline(self):
+        self.assertEqual(sigutils.dbg_signal(self.signal, ['foo\nbar']),
+                         'fake(foo bar)')
+
 
 if __name__ == '__main__':
     unittest.main()

qutebrowser/utils/signals.py

@@ -19,6 +19,8 @@
 
 import re
 
+from qutebrowser.utils.misc import elide
+
 
 def signal_name(sig):
     """Get a cleaned up name of a signal.
@@ -43,4 +45,5 @@ def dbg_signal(sig, args):
     Return:
         A human-readable string representation of signal/args.
     """
-    return '{}({})'.format(signal_name(sig), ', '.join(map(str, args)))
+    argstr = ', '.join([elide(str(a).replace('\n', ' '), 20) for a in args])
+    return '{}({})'.format(signal_name(sig), argstr)